<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>继承</title>
</head>
<body>
    <div>
        <h1>一级标题</h1>
        <p>这是一段文字</p>
    </div>
    <div>
        <h2>这是二级标题</h2>
    </div>
    <style>
        body{
            color: cadetblue;
        }
        div:first-child{
            color: brown;
        }
    </style>
</body>
</html>